platypush/runbullet/__init__.py

import functools
import importlib
import os
import logging
import json
import socket
import subprocess
import sys
import time
import websocket
import yaml

from queue import Queue
from threading import Thread
from getopt import getopt

__author__ = 'Fabio Manganiello <info@fabiomanganiello.com>'

#-----------#

config = {}
modules = {}
wrkdir = os.path.dirname(os.path.realpath(__file__))


def _init_plugin(plugin_name, reload=False):
    global modules
    global config

    if plugin_name in modules and not reload:
        return modules[plugin_name]

    try:
        module = importlib.import_module(__package__ + '.plugins.' + plugin_name)
    except ModuleNotFoundError as e:
        logging.warn('No such plugin: {}'.format(plugin_name))
        raise RuntimeError(e)

    # e.g. plugins.music.mpd main class: MusicMpdPlugin
    cls_name = functools.reduce(
        lambda a,b: a.title() + b.title(),
        (plugin_name.title().split('.'))
    ) + 'Plugin'

    plugin_conf = config[plugin_name] if plugin_name in config else {}

    try:
        plugin = getattr(module, cls_name)(plugin_conf)
        modules[plugin_name] = plugin
    except AttributeError as e:
        logging.warn('No such class in {}: {}'.format(
            plugin_name, cls_name))
        raise RuntimeError(e)

    return plugin


def _exec_func(args, retry=True):
    action = args.pop('action')
    tokens = action.split('.')
    module_name = str.join('.', tokens[:-1])
    method_name = tokens[-1:][0]

    try:
        plugin = _init_plugin(module_name)
    except RuntimeError as e:  # Module/class not found
        logging.exception(e)
        return

    try:
        ret = plugin.run(method=method_name, **args)
        out = None
        err = None

        if isinstance(ret, list):
            out = ret[0]
            err = ret[1] if len(ret) > 1 else None
        elif ret is not None:
            out = ret

        if out:
            logging.info('Command output: {}'.format(out))

        if err:
            logging.warn('Command error: {}'.format(err))
    except Exception as e:
        logging.exception(e)
        if retry:
            # Put the action back where it was before retrying
            args['action'] = action

            logging.info('Reloading plugin {} and retrying'.format(module_name))
            _init_plugin(module_name, reload=True)
            _exec_func(args, retry=False)


def on_msg(msg):
    Thread(target=_exec_func, args=(msg,)).start()


def parse_config_file(config_file=None):
    global config

    if config_file:
        locations = [config_file]
    else:
        locations = [
            # ./config.yaml
            os.path.join(wrkdir, 'config.yaml'),
            # ~/.config/runbullet/config.yaml
            os.path.join(os.environ['HOME'], '.config', 'runbullet', 'config.yaml'),
            # /etc/runbullet/config.yaml
            os.path.join(os.sep, 'etc', 'runbullet', 'config.yaml'),
        ]

    for loc in locations:
        try:
            with open(loc,'r') as f:
                config = yaml.load(f)
        except FileNotFoundError as e:
            pass

    return config


def get_backends(config):
    backends = []

    for k in config.keys():
        if k.startswith('backend.') and (
                'disabled' not in config[k] or not config[k]['disabled']):
            module = importlib.import_module(__package__ + '.' + k)

            # e.g. backend.pushbullet main class: PushbulletBackend
            cls_name = functools.reduce(
                lambda a,b: a.title() + b.title(),
                (module.__name__.title().split('.')[2:])
            ) + 'Backend'

            try:
                b = getattr(module, cls_name)(config[k])
                backends.append(b)
            except AttributeError as e:
                logging.warn('No such class in {}: {}'.format(
                    module.__name__, cls_name))
                raise RuntimeError(e)

    return backends

def get_device_id():
    global config
    return config['device_id']


def main():
    DEBUG = False
    config_file = None

    plugins_dir = os.path.join(wrkdir, 'plugins')
    sys.path.insert(0, plugins_dir)

    optlist, args = getopt(sys.argv[1:], 'vh')
    for opt, arg in optlist:
        if opt == '-c':
            config_file = arg
        if opt == '-v':
            DEBUG = True
        elif opt == '-h':
            print('''
Usage: {} [-v] [-h] [-c <config_file>]
    -v  Enable debug mode
    -h  Show this help
    -c  Path to the configuration file (default: ./config.yaml)
'''.format(sys.argv[0]))
            return

    config = parse_config_file(config_file)
    logging.info('Configuration dump: {}'.format(config))

    if 'device_id' not in config:
        config['device_id'] = socket.gethostname()

    if 'debug' in config:
        DEBUG = config['debug']

    if DEBUG:
        logging.basicConfig(level=logging.DEBUG)
        websocket.enableTrace(True)
    else:
        logging.basicConfig(level=logging.INFO)

    mq = Queue()
    backends = get_backends(config)

    for backend in backends:
        backend.mq = mq
        backend.start()

    while True:
        try:
            on_msg(mq.get())
        except KeyboardInterrupt:
            return

if __name__ == '__main__':
    main()

# vim:sw=4:ts=4:et: